The device of this invention resides in the area of cartridges having nozzles and foil seals located at the bottom of such nozzles, such cartridges containing a variety of filler materials such as a caulking material, adhesive and the like, such cartridges, after the top of the nozzle has been opened and the foil seal broken, to be inserted into a gun for the application of its contents through the nozzle when the gun""s plunger is advanced by action of its trigger, and more particularly relates to an improved nozzle having built-in means for piercing the foil seal.
Cartridges containing a wide variety of flowable material, such as caulking material and adhesives, are well known in the industry. Such cylindrical cartridges have nozzles at their top end and, after opening, such cartridges are inserted into guns wherein a plunger is advanced therein by action of squeezing a trigger, causing material in the cartridge to flow out through the nozzle to the area where it is to be applied. Some cartridges have a foil seal under the nozzle against which seal the material can be positioned. Some materials, if exposed to air, will harden, so that by providing such a seal, air contact with the materials before the cartridge is opened is minimized. To open a cartridge having a foil seal, one must first snip off the tip of the plastic nozzle and then insert an object down the nozzle to puncture the foil seal located at the bottom of the nozzle to allow the passage of the filler material out of the cartridge. It is sometimes difficult to locate a narrow enough instrument to insert down the open nozzle tip to puncture the foil seal. Further, if one snips off the nozzle tip to leave a small diameter opening to achieve a fine application bead of material and one does not have an instrument narrow enough to pass down through the opening in the nozzle to puncture the foil seal, one can undesirably stretch the nozzle tip by using a larger object, making it difficult to apply a narrow bead of material as the now-wider opening in the nozzle tip will allow a wider-than-desired bead of material to pass out the nozzle.
Cartridges filled with a variety of filler materials are commonly sold. The tops of such cartridges including their nozzles are formed of plastic. The top is spun within the barrel to effect a heat seal with the sides of the barrel. Nozzle tops are also made in two parts wherein plastic nozzle top is press fit into a metal crimpable end cap, forming a nozzle top which can be crimped onto a paperboard barrel. The foil seal of a cartridge is located beneath the central bore of the nozzle which foil seal prevents the premature escape of the filler material when the cartridge is loaded in the gun and also prevents such material from drying out and hardening within the cartridge. The tip of the cartridge nozzle is often initially sealed and must be snipped off at a desired point along the tapered nozzle to effect the desired shape of opening to create the size of the bead of material which will be applied by the user.
My own patent, granted to Paul D. Jackman, U.S. Pat. No. 6,029,856, issued on Feb. 29, 2000, hereafter referred to as xe2x80x9cmy prior patentxe2x80x9d describes a self-puncturing cartridge nozzle. The devise of my prior patent requires that the user manually bend the nozzle laterally in relation to nozzle base which motion causes a sharpened edge located at the inside of the base of the nozzle to cut through the foil seal.
Normally cartridge nozzles are opened by first snipping the tip off at a certain distance from the tapered end to achieve a specific bead width. A disadvantage of my prior patent is that the user is also required to bend the nozzle to a specific point whereby the foil seal is punctured. This manual opening procedure related to the foil seal must be communicated to the user in writing on the cartridge body of specific instructions regarding it. The above describes a two step opening procedure.
Disadvantages of my prior patent:
(a) Two separate steps are required to open the cartridge.
(b) A user may inadvertently bend the nozzle too far and possibly fracture plastic at base of nozzle.
(c) A user may not bend the nozzle far enough to sufficiently puncture the foil seal.
(d) A cartridge may be dropped accidentally causing nozzle to bend and puncture foil seal before it was intended to be opened possibly causing contents to leak or dry out.
(e) Softer, pliable plastic compounds required to allow nozzle to be flexible may be too weak for requirements in shipping, handling, vertical stacking, and other manufacturing procedure.
(f) Foil seals could be punctured by persons tampering with cartridges at retail locations which could cause filler material to dry out.
It is the object of this invention to provide a cartridge for containing various filler materials having a nozzle tip and a foil seal thereunder with self contained means to puncture foil seal by pressurizing filler material to allow the passage through the nozzle of the contents of the cartridge.
To accomplish this result, the plastic nozzle top of the cartridge is formed with a downwardly extending sharp edge disposed above the foil seal. When the contents of the cartridge is pressurized, the foil seal is forced by such pressure into the sharp edge at the base of the nozzle causing the foil seal to puncture and thereby allow the contents of the cartridge to pass through the opened tip of the nozzle for application.
It is yet a further object of this invention to provide an improved nozzle to a cartridge barrel which is molded of plastic which can be easily substituted for prior art nozzle tops during the manufacture of cartridges without any other changes to the product required and which can be entirely molded of one piece of plastic.
It is yet a further object of this invention to provide an improved nozzle top to a cartridge which can be press fit into a crimpable metal end cap.